Re: 2.4Ghz 40Mhz 802.11n wifi and Apple Macbook

[Mike Hammett <nanog () ics-il net>]

It'd be nice if IEEE would start supporting smaller channel sizes and a sync method in the 802.11 specifications. make 
the default channel size 5 MHz and it auto increases as necessary. 20 meg Internet could get by just fine on 
interference free 5 MHz. Have a 1588-like sync mechanism sent from the ISP for residential (or your controller for 
public\business use) to have them transit in sync as well to reduce interference. 




----- 
Mike Hammett 
Intelligent Computing Solutions 
http://www.ics-il.com 

----- Original Message -----

From: "Josh Reynolds" <josh () spitwspots com> 
To: outsider () scarynet org 
Cc: nanog () nanog org 
Sent: Sunday, June 14, 2015 11:06:12 PM 
Subject: Re: 2.4Ghz 40Mhz 802.11n wifi and Apple Macbook 

40MHz on 2.4 is note widely supported, and for good reason - it sucks up the entire unlicensed 2.4GHz band (if you 
include the 802.12 mask). 

On 5GHz, 20/40 are supported, and 80/160 in current and future versions of 802.11ac. 

On Jun 14, 2015 7:56 PM, Alexander Maassen <outsider () scarynet org> wrote: 
> Shoot me if i'm wrong, but doesn't a mac prefer MIMO in order to work 
> correctly? 
>
> On Sun, June 14, 2015 8:42 pm, Brielle Bruns wrote: 
> > On 6/14/15 12:33 PM, Anurag Bhatia wrote: 
> > > Hello everyone, 
> > >
> > >
> > >
> > > I am running a TP Link TL-WR1043N which (as TP Link says is a) 802.11n 
> > > router working on 2.4Ghz (no support for 5Ghz). I am running it with 
> > > flashed OpenWRT. 
> > >
> > >
> > >
> > > While using option to pick 40Mhz, I see my Mac only gets 20Mhz to use 
> > > and 
> > > speed is always 130Mbps. There's no other SSID nearby and I am sitting 
> > > next 
> > > to router for testing. 
> > >
> > >
> > > This brings me to question - Has anyone successfully used 40Mhz with 
> > > 2.4Ghz 
> > > on 802.11n standard with Apple Macbook? I wonder if it's limitation on 
> > > the 
> > > chipset or something else. 
> >
> > Everything that I've seen/experienced says that Apple devices won't use 
> > 40mhz channels with 2.4 due to the overlapping bands/lack of good 
> > separation between channels. 
> >
> > However, I'm not sure if this specifically applies to just the Airport 
> > APs like the Extreme, or to the laptops as well, as I use AE's at home, 
> > and the Unifi APs I do have in service all have 20mhz channels only set 
> > on them to avoid issues. 
> >
> >
> > -- 
> > Brielle Bruns 
> > The Summit Open Source Development Group 
> > http://www.sosdg.org / http://www.ahbl.org